What it is and what it does
The Siemens 3RH1122-1AL00-0AA6 is a SIRIUS auxiliary contactor in the S00 frame size, designed to switch control and signaling circuits rather than motor loads directly. Its two normally-open instantaneous contacts handle 10 A at 24 V, with a surge voltage resistance of 6 kV — enough isolation for most 24 VDC control loops in a panel. The contact reliability spec of one incorrect switching operation per 100 million operations at 17 V, 1 mA means it is trustworthy for PLC input dry-contact feedback even at low signal levels.
Mounting and integration
Fastens via screw and snap-on mounting onto a DIN rail — the S00 footprint is 45 mm wide, 57.5 mm tall, and 72 mm deep. The mounting position is flexible: +/-180° rotation on a vertical surface, and can be tilted forward/backward by +/-22.5°. Accepts solid wire from 0.5 to 4 mm² — spring-cage or screw terminals depending on variant, but this order code uses screw-type. IP20 on the front means it is protected against finger contact but not washdown; keep it inside a closed panel.
Environmental and mechanical limits
Rated for operation from -25 to +60 °C, storage and transport from -55 to +80 °C. Shock resistance is 10 g for 5 ms and 5 g for 10 ms — fine for normal industrial vibration but not heavy hammering. Pollution degree 3 means it tolerates conductive pollution in a typical control cabinet environment.